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MOTOR THERMISTOR INTERFACE
6
6.3.3 Activating the motor thermistor
Set
Pr.407
≠
"9999" to activate the motor thermistor. Activation of the motor thermistor enables thermal
protection of the motor and slip compensation.
⋅
Normally set about "30s" in
Pr.407
.
⋅
When the response is slow to the motor temperature, set a smaller value.
(1) Thermal protection of the motor
⋅
When the motor temperature remains at 145°C or higher for 10s, motor overload trip (E.THM) activates
to shut off the inverter output.
⋅
When the motor temperature goes to -30°C or lower during operation, motor overload trip (E.THM)
activates to shut off the inverter output. Motor overload trip (E.THM) does not occur during a stop.
(2) Slip compensation (R2 compensation)
Slip compensation (R2 compensation) is available during vector control.
Slip frequencies are compensated according to temperatures detected by the thermistor.
CAUTION
⋅
When operation is performed with the thermal protection function valid without a thermistor or in the
calibration status, protection function activates to shut off the inverter output.
⋅
Since a dedicated motor with thermistor has no thermal protector, always set a value other than "9999" in
Pr.407 Motor temperature detection filter
to make the thermal protection function valid.
When the setting remains "9999", motor protection is not activated. (Electronic thermal O/L relays operate
following the current value set in
Pr.9 Electronic thermal O/L relay
.)
REMARKS
⋅
Setting
Pr.407
≠
"9999" disables the magnetic flux observer setting (
Pr.95
= "2").
